Before Cassini arrived at the Saturn system, planetary explorers had only hints that something interesting might be happening at Enceladus. Now our Enceladus discoveries have changed the direction of planetary science.

This collage of images from NASA's Cassini spacecraft shows Saturn's northern hemisphere and rings as viewed with four different spectral filters. Each filter is sensitive to different wavelengths of light and reveals clouds and hazes at different altitudes.

Surface features are visible on Saturn's moon Prometheus in this view from NASA's Cassini spacecraft. Most of Cassini's images of Prometheus are too distant to resolve individual craters, making views like this a rare treat.

Saturn appears as a serene globe amid tranquil rings in this view from NASA's Cassini spacecraft. In reality, the planet's atmosphere is an ever-changing scene of high-speed winds and evolving weather patterns, punctuated by occasional large storms.

Two tiny moons of Saturn, almost lost amid the planet's enormous rings, are seen orbiting in this image. Pan, visible within the Encke Gap near lower-right, is in the process of overtaking the slower Atlas, visible at upper-left.

Cassini looks toward the brilliant disk of Saturn, surrounded by the icy lanes of its rings. Faint wisps of cloud are visible in the atmosphere. At bottom, ring shadows trace delicate, curving lines across the planet.

On Tuesday, Sept. 20, 2016, the Cassini spacecraft took its final optical navigation, or OpNav, image of the mission. Throughout its journey Cassini has used its narrow angle camera to capture images of Saturn’s moons against backgrounds of known stars to precisely determine the spacecraft’s course, as well as the moon’s. In all, the spacecraft has taken 2,817 images solely for navigation purposes since launching in 1997.

Since NASA's Cassini spacecraft arrived at Saturn in mid-2004, the planet's appearance has changed greatly. The shifting angle of sunlight as the seasons march forward has illuminated the giant hexagon-shaped jet stream around the north polar region, and the subtle bluish hues seen earlier in the mission have continued to fade.

Saturn's shadow stretched beyond the edge of its rings for many years after Cassini first arrived at Saturn, casting an ever-lengthening shadow that reached its maximum extent at the planet's 2009 equinox. This image captured the moment in 2015 when the shrinking shadow just barely reached across the entire main ring system.

This synthetic-aperture radar (SAR) image was obtained by NASA's Cassini spacecraft on July 25, 2016, during its "T-121" pass over Titan’s southern latitudes. This view was produced using the same radar data as PIA20712, but the radar data have been treated with a technique for handling noise that can result in clearer, easier to interpret views.

This synthetic-aperture radar (SAR) image was obtained by NASA's Cassini spacecraft on July 25, 2016, during its "T-121" pass over Titan’s southern latitudes. See PIA20713 for an alternate version of this image using a different processing technique.

In the Shangri-La Sand Sea on Titan is shown in this image from the Synthetic Aperture radar (SAR) on NASA's Cassini spacecraft. See PIA20711 for an alternate version of this image using a different processing technique.